Purpose of namespace in C#

In adittion to other answers:

 

You can think of namespace as a logical container, i am saying it logical because it has no physical signification.

if you create a physical folder and puts multiple files then that folder can be considered as a container for those files.

similarly, .NET provides us a way to define a logical container so that we can put all our related classes inside that so that later we can access those classes using the namespace with the "using statement" at the top.

 

Generally, when we create a project then we forget to give any meaningful name to namespace and by default, the project name becomes the namespace name that is why later when we create another class library project / any project then after adding the reference to the first project we need to use the first project name in the using statement to access classes of the first project as the namespace.